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1.
The problems associated with the conversion of commercial carboxylic acid ion exchangers to the acid chloride have been studied and a synthesis of a cross-linked poly(acryloyl chloride) is described. Reaction with phenylhydroxylamine produced a chelating ion exchanger, possessing acyl oxime functional groups, whose properties are compared with those of an aroyl oxime exchanger described earlier. Resin capacity from the acyl oxime group was 0.45 mmole g-1, and the resin had a rapid equilibration rate. A column separation of mercury and lead is discussed.  相似文献   

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Chelating ion exchangers containing N-carbonylphenylhydroxylamine functional groups have been synthesized and their exchange behaviour with copper, cobalt, iron, vanadium and uranium investigated. Of the two polymers described, a linear oxime-carbonyl polymer exhibited chelating capacity as a function of pH analogous to the chelates formed by BPHA. An oxime-carbonyl polymer based on polyethyleneimine had high capacities for the metal ions studied, but the principal mode of reaction was by electron donation from nitrogen atoms. The absence of co-ion in metal ion capacity studies indicates the possibility of formation of 1:2 and 1:3 metal complexes with the resin. Separations of iron(II)-iron(III) and vanadium-iron appear possible.  相似文献   

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Summary Uranium or thorium separations from a number of various ions were studied by means of cation exchangers containing phosphorus in their functional group. These ion exchangers adsorb selectively only UO2 2+ or Th4+ ions from the mixture studied in a medium of >0.4 N nitric or hydrochloric acid. Several di- and trivalent cations are not sorbed under these conditions. In the absence of UO2 2+ and Th4+ ions, Me2+ may be more easily separated quantitatively from Me3+ in 0.2 N nitric or hydrochloric acid than with cation exchangers containing the -SO3H group.
Zusammenfassung Die quantitative Trennung von UO2 2+ oder Th4+ von einer Reihe anderer Ionen wurde mit Hilfe phosphorhaltiger Kationenaustauscher untersucht. Diese Ionenaustauscher sorbieren selektiv nur UO2 2+ oder Th4+-Ionen aus einem Medium von >0,4 N HNO3 oder HCl. Eine Reihe verschiedener zwei- und dreiwertiger Kationen wird unter diesen Bedingungen nicht sortiert. Bei Abwesenheit von UO2 2+- und Th4+-Ionen kann man Me2+ in 0,2 N HNO3- oder HCl-Lösung quantitativ von Me3+ trennen, und zwar leichter als mit -SO3H-haltigen Austauschern.
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Ion exchange separations on a new hydroxamic acid ion exchanger are described. Quantitative separation of iron(III) from various salts and from several analytical standards has been achieved, and sources of interference in the colorimetric determination of iron with thioglycollic acid can be eliminated. Quantitative separations of copper from iron and from cobalt and nickel are possible. Recoveries and separations of iron and uranium from simulated sea-water samples are demonstrated.  相似文献   

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The C=C bond plays numerous roles in polymer science. This moiety is used as a precursor to polymers by addition polymerization and has been incorporated into π-conjugated polymers. The addition polymerization reaction has been extended to P=C bonds and the first example of a poly(methylenephosphine) has been prepared. The new macromolecule is of moderate molecular weight (ca. 104 g/mol) and the oxidized polymers are air-stable. Poly(p-phenylenephosphaalkene), the first π-conjugated polymer containing P=C bonds in the backbone, has been prepared. The UV/Vis spectrum of this polymer shows a red shift in λmax when compared with molecular model systems.  相似文献   

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The sorption and desorption characteristics of gold and silver on a polyhydroxamic acid chelating resin are described. Gold is quantitatively sorbed from 0.5 M nitric acid or neutral solutions, and readily eluted with 0.5% (wv) potassium cyanide solution. Silver is removed from 0.05 M nitric acid or neutral solutions, and can be eluted with the cyanide solution or with 0.5 M nitric acid. Gold can be quantitatively separated from copper, iron and silver; gold and silver are sorbed from dilute cyanide solutions. Tests with river water and other eluting systems are reported.  相似文献   

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The synthesis of a cross-linked polystyrene-azo-PAR resin, and its chelating ion-exchange properties with nine ionic species, are described. A resin structure, containing both PAR and azophenol chelating groups is proposed. The effects on capacity of varying ionic concentration and the nature of the co-ion were studied.  相似文献   

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The separation of iron(III), copper(II) and uranyl(II) ions from a series of salt solutions by chelating ion exchange on Duolite CS-346 resin by pH control is described. Recoveries of these ions from cobalt and nickel salt solutions were quantitative. Iron may also be separated from copper by selective sorption with pH control, and uranium from iron and copper by selective desorption with sodium carbonate solution as eluent.  相似文献   

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In this work, colloidal spheres composed of azo polymers with different chromophore loading densities were prepared, and their photoinduced deformation behavior was studied. The colloids were constructed by using a series of amphiphilic epoxy-based random copolymers containing 4-carboxylazobenzene functional groups with different degrees of functionalization (DFs). The colloidal spheres were fabricated through gradual hydrophobic aggregation of the polymeric chains in tetrahydrofuran-H2O dispersion media, which was induced by gradually adding water into the systems. The colloidal spheres were characterized by using transmission electron microscopy and dynamic light scattering. The photoinduced deformation behavior was studied by irradiating the colloidal spheres with a linearly polarized Ar+ laser beam. Results showed that the critical water content (CWC) for the colloid formation is related to the DF of the polymers, and CWC increases with the increase of DF. The hydrodynamic diameter of the colloidal spheres is also related to the DF of the polymers. When the DF of the polymers increases, the average size of the colloids gradually decreases. The hydrodynamic diameter of the colloidal spheres increases as the water dropping rate decreases. When the dropping rate is below 20 microL/s, the size of the colloidal spheres increases abruptly as the dropping rate further decreases. Upon the linearly polarized Ar+ laser beam irradiation, the colloids composed of polymers with different DFs can all be elongated along the polarization direction of the laser beam. As DF increases, the deformation degree characterized by the axial ratio (l/d) almost linearly increases. These observations can give some insight into the photoinduced deformation mechanism and can be used to construct colloids with different sizes and photoresponsive ability.  相似文献   

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